'77 Johnny 140 hp carbs.

[87Aggie]

I must have messed something up somewhere when I rebuilt the carbs on my 140 hp. I was having a poor idling problem and had never rebuilt the carbs so I decided to give it a shot after reading several posts here and figuring it wasn't too difficult. Before the rebuild, I would pump up the ball and it would get firm, however, it seemed like a lot of fuel always "flooded" out the front of the carbs and into the air silencer and then down to the pan and into my boat (very messy). After the rebuild it still does this. I feel pretty confident that I set the floats correctly. Any ideas?

 

[steviecops]

Re: '77 Johnny 140 hp carbs.

Did you use a new inlet needle and valve assembly?

 

[87Aggie]

Re: '77 Johnny 140 hp carbs.

Yes, it was a Sierra kit with all the gaskets and everything. The only thing it didn't come with was new floats and jets.

 

[jy118lfd]

Re: '77 Johnny 140 hp carbs.

Did you replace the needle and seats when you rebuilt the carbs? Or are you talking about when you tilt the motor that the silencer gets full of gas. If its when you tilt the motor that you get the fuel problem it could be the silencer gasket or the hose at the bottem of the silencer that is supposed to drain the gas that leaks out of the carbs when you tilt the motor back into the motor. If it comes off the reed plate it can be a slight pain to get back on. A long pair of needle nose usually works good. If the gasket is good between the siclencer and cover the plastic cover could be warped.

 

[87Aggie]

Re: '77 Johnny 140 hp carbs.

As I mentioned to steviecops, I did replace the needle and seats. The fuel leaks when its level and especially when I tilt it up. I've replaced the silencer gasket and checked the drain hose you mentioned also, it still leaks out pretty bad. I've never really noticed where it leaks out but I'm pretty sure its between the silencer and gasket. Should that much gas come out of the carburetor though?

 

[steviecops]

Re: '77 Johnny 140 hp carbs.

How does the engine run? Do you think it's flooding?<br /><br />If it is flooding and you've got new inlet needles and valves in them, then the floats can't be set right. <br /><br />Might be worth checking the fuel line connections to make sure fuel isn't leaking from there, and also check to see if there is a leak around the bowl gaskets. Maybe one of the bowls is warped or cracked?<br /><br />Good luck.<br />Steve

 

[jy118lfd]

Re: '77 Johnny 140 hp carbs.

No gas should come out of the carbs when level. I would take the scilencer and cover off to expose the carbs. Pump the bulb and see where the gas leaks from. If it comes from the carb throat and the bulb never gets hard then you have a bad needle and seat or float. I just did the carbs on my v6 crossflow and with a brand new needle and seat. I got a piece of hose that got stuck in one needle and seat and had to take it apart again. So you might have a piece of dirt in a new one. It only takes a small piece to stop them from closing. Hang in there you will find the problem it just takes some investigating.

 

[strib]

Re: '77 Johnny 140 hp carbs.

the fuel overage is probably coming up the emulsion tube.lower the fuel bowl level by bending the float tang.

 

[87Aggie]

Re: '77 Johnny 140 hp carbs.

Steviecops, good question. I'm not able to get the darn thing started, no fire. I had this problem earlier last summer. I replaced the stator, powerpack and rectifier and cleaned and tightened all ground wires that I could find. Miraculously, it fired up one day and was fine for the rest of the summer. During that time the motor ran fine except for a very poor idle and occasional hard starting. Before all the replacements, I had rebuilt the carbs and linked/synced according to the book (OMC manual).<br />I parked it about a month ago and was getting it ready for the winter when the no start progrem recurred, no fire as I said earlier. I'm ready to put a bullet in her!!

 

[steviecops]

Re: '77 Johnny 140 hp carbs.

As far as the fuel problem goes, it does sound like it's flooding. What with the hard starting and poor idle, plus the fuel leaking out of the carbs. So It would be worth taking them off and checking the needles and seats for dirt, like Jon Yarh says, and checking that the floats are set at the correct level and have the correct amount of drop. Make sure that the main nozzle gasket is the correct one. See if you can see marks on it where it has been compressed between the two halves of the carbs.<br /><br />As for the spark problem, well you've replaced everything except the ignition coils. Are you getting a spark on any of the cylinders, or none at all?

 

[87Aggie]

Re: '77 Johnny 140 hp carbs.

Not getting spark on any. Can't imagine that all the coils would go bad at the same time. I plan on checking the flywheel this weekend to make the key isn't sheared. A sheared key would attribute to a no fire situation wouldn't it? As you mentioned, another project will be the carb dismantle and check. I've been talking with walleyehed about OEM sealant type M, which I didn't use on the rebuild last time. I'm looking for some or its equivalent when I rebuild it this time. Does anyone know if it gets used on all the gaskets? I don't recall the manual mentioning using it at all, but I may be wrong.

 

[jy118lfd]

Re: '77 Johnny 140 hp carbs.

87 disconnect the red connector at the motor and jump the solenoid if you now have spark the ignition switch is bad. If it starts you must choke it to shut it off! Lets get the spark problem fixed first then move on from there.

 

[steviecops]

Re: '77 Johnny 140 hp carbs.

Ditto Jon Yahr on getting the spark problem sorted out first.<br /><br />I believe that Joe reeves has posted on here about disconnecting the yellow/black lead from the powerpack, (that's the kill switch lead), and testing for a spark. If you get a spark with that lead disconnected, it could just be the lead shorted to ground somewhere. You don't want to go replacing your switch if you don't have to.<br /><br />To be certain, (I might have got some of the details mixed up), I'd do a search for Joe's post.

 

[jy118lfd]

Re: '77 Johnny 140 hp carbs.

steviecops you are right it could be the wire with an open circut not just the switch. I ment to say it is most likely the switch. I had to get off line in a hurry I am a firefighter like you and the bell rang here at work so off we went

 

[steviecops]

Re: '77 Johnny 140 hp carbs.

Nothing serious I hope Jon.<br /><br />Internet access at work! They give us computers now in the London Fire Brigade, but they don't trust us with internet access!